package com.googlecode.t7mp;
   
   import java.util.List;
   
   import com.google.common.collect.Lists;
   
   import edu.emory.mathcs.backport.java.util.concurrent.atomic.AtomicInteger;
   
   /**
   * 
   * 
   * 
   * @author Joerg Bellmann
   *
   */
  public final class InstanceConfigurationUtil {
  
      private InstanceConfigurationUtil() {
          //hide constructor
      }
  
      public static List<InstanceConfiguration> createInstanceConfigurations(DefaultMavenPluginContext mavenPluginContext) {
          validateInstanceCount(mavenPluginContext.getConfiguration().getInstanceCount());
          final int configuredHttpPort = mavenPluginContext.getConfiguration().getTomcatHttpPort();
          final int configuredShutdownPort = mavenPluginContext.getConfiguration().getTomcatShutdownPort();
          final String configuredCatalinaBasePath = mavenPluginContext.getConfiguration().getCatalinaBase().getAbsolutePath();
          List<InstanceConfiguration> configurations = Lists.newArrayList();
          for (int i = 0; i < mavenPluginContext.getConfiguration().getInstanceCount(); i++) {
              InstanceConfiguration coniguration = new InstanceConfiguration(i, new AtomicInteger(configuredHttpPort).addAndGet(i), new AtomicInteger(
                      configuredShutdownPort).addAndGet(i), configuredCatalinaBasePath + i);
              configurations.add(coniguration);
          }
          // validate ports
          validatePorts(configurations);
          return configurations;
      }
  
      private static void validatePorts(List<InstanceConfiguration> configurations) {
          List<Integer> ports = Lists.newArrayList();
          for (InstanceConfiguration configuration : configurations) {
              if (ports.contains(new Integer(configuration.getHttpPort()))) {
                  throw new TomcatSetupException("We have conflicting ports ...");
              } else {
                  ports.add(new Integer(configuration.getHttpPort()));
              }
              // shutdown ports
              if (ports.contains(new Integer(configuration.getShutdownPort()))) {
                  throw new TomcatSetupException("We have conflicting ports ...");
              } else {
                  ports.add(new Integer(configuration.getShutdownPort()));
              }
          }
      }
  
      private static void validateInstanceCount(int instanceCount) {
          if (instanceCount < 1) {
              throw new TomcatSetupException("InstanceCount property should not be smaller than 1");
          }
      }
  
  }